docs: def logs(self, num=None, source=None, ps=None, tail=False):
          """Returns the requested log."""
  
          # Bootstrap payload package.
          payload = {'logplex': 'true'}
  
          if num:
              payload['num'] = num
  
          if source:
              payload['source'] = source
  
          if ps:
              payload['ps'] = ps
  
          if tail:
              payload['tail'] = 1
  
          # Grab the URL of the logplex endpoint.
          r = self._h._http_resource(
              method='GET',
              resource=('apps', self.name, 'logs'),
              data=payload
          )
  
          # Grab the actual logs.
          r = requests.get(r.content.decode("utf-8"), verify=False, stream=True)
  
          if not tail:
              return r.content
          else:
              # Return line iterator for tail!
              return r.iter_lines()